AC vs. whole house dehumidifier
Hello, I am looking for some advice on a central AC system vs. a whole house dehumidifier. My house is located in Upstate NY (zone 6A) it’s a two story, 1700 sq ft, 2×6 stick built home, built in 1998. Nothing too fancy in terms of energy efficient construction, but it’s not horrible either. Overall, the house and area is humid. We have lots of shade, the entire house is surrounded by 100 foot tall white pines and there are wetlands a few hundred feet behind the house.
When we moved in four years ago we had lots of window condensation during shoulder seasons. To rectify this, we have installed downspout extensions on all the gutters, a bathroom fan in each bathroom (one that runs most of the year at a low 50 cfm), a portable dehumidifier in the basement that is set at 55% and runs about 8 months a year (about one full bucket per 24 hrs in the summer), and a kitchen hood that vents outside. All of these helped and window condensation is all but gone, but our house is still routinely above 60% humidity inside. As I type this now, it is 73 degrees inside with 83% humidity (the last two days have been uncommonly hot and humid for this time of year), but those temps and humidity levels are very common July-Sept.
Therefore, I am thinking of replacing our old/broken central AC system or purchasing a whole house dehumidifier. With the AC unit, I am a bit afraid that we would have to make the house an ice box to properly dehumidify it. Many days it is not too hot inside (low to mid 70’s), but the humidity is 70-80% inside. Does that make a whole house dehumidifier make more sense?
What about AC units with “Dry” or dehumidify mode? Are those only available in two stage units?
Or should I at first try running a portable dehumidifier on the main level in addition to the basement?
Any comments or thoughts would be appreciated.
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